Luis Severino of the Yankees pitches against the Mets at Citi Field on Aug. 17, 2017. Photo Credit: Jim McIsaac

It seemed unfathomable at the time that there could be some good to Luis Severino’s year. It was 2016, and he labored and lost. He struggled terribly as a starter, his spot with the Yankees was called into question, and with Severino at the ripe old age of 22, some wondered if he was destined to be a disappointment.

But that was the past. Severino rebounded in 2017. Last month, CC Sabathia even called him the Yankees’ ace.

If Severino learned anything from the most difficult year of his career, it was on full display Thursday night at Citi Field. In his first start since being charged with a career-high 10 runs in 4 1⁄3 innings against the Red Sox (eight earned), he proved he has mastered something that many players his age struggle with.

It appears Severino has learned how to fail — or, perhaps more correctly, how to not let past failure dictate future results.

Severino zipped through the Mets’ lineup with the confidence of someone with a very short memory Thursday night, and his team cruised until Bryan Mitchell made it a ballgame by allowing Curtis Granderson’s grand slam in the ninth inning of the Yankees’ 7-5 victory.

“A lot of times in life, you grow more through your struggles than through your success,” Joe Girardi said. “The year before he came up — 2015 — and really burst on the scene, he didn’t really struggle a whole lot. Last year, he went through his struggles and figured out what he needed to do to be really successful at this level over and over . . . Sometimes you have to make adjustments, and that’s what he learned how to do last year, and I think it helps him make an adjustment after a poor start.”

Severino walked three Mets, but with a ground-ball percentage that ranks third in the AL, it didn’t cause too much of a problem. His slider and changeup appeared sharper, his fastball placement more exact.

“I wasn’t ahead of the count almost all of the time [in the previous start], so I tried to do that,” Severino said. “I think the last time, the third inning, I tried too [hard] to pitch around the batters, so this time, I just went after everyone.”

He also recorded his first major-league hit, a semi-popped-up sacrifice bunt that got past the diving Dominic Smith in the fourth inning to load the bases with none out, much to the delirious delight of his teammates. He scored the Yankees’ sixth run on Gary Sanchez’s two-run single.

Severino was 0-8 with an 8.50 ERA as a starter last season but then starred as a reliever, going 3-0 with an 0.39 ERA. And on Thursday night, he returned to his 2017 form, giving the Yankees confidence that a bad start doesn’t necessarily mean a regression to the Severino of old. Before that start against the Red Sox, he was 4-0 with a 0.83 ERA since the All-Star break.

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The only run he gave up Thursday night came courtesy of Aaron Judge, who dropped a one-out fly ball to land Travis d’Arnaud at second in the seventh. Matt Reynolds drove him in with a single. Brandon Nimmo also singled, and Severino exited to applause from the Yankees fans situated behind the visiting dugout.

It was a poised, successful start, and really not all that surprising. One year after that terrible season, Severino is the youngest Yankees All-Star since Mel Stottlemyre in 1965. He’s withstood failure and disappointment and months of being booed to come out the other side, and on Thursday night, he simply showed how far he’s come and how much he’s learned along the way.

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